Device for regulating the rate of flow of the air blown into the exhaust duct of an internal combustion engine

Claim 2

An internal combustion engine comprising an intake piping, an exhaust piping, a pump driven by the engine for drawing air from the atmosphere and discharging through a delivery duct the compressed air into said exhaust piping, means for varying the rate of delivery though said delivery duct, the improvement including first means sensitive to the differential between the pressure in the delivery duct of the pump and the pressure in the exhaust piping, said first means being connected to said means for varying the rate of delivery in the sense of diminishing said rate of flow as the differential is increased, second means sensitive to the differential between one at least of said pressures in the exhaust piping and in the delivery duct and the outside atmosphere pressure; said second means being connected to said means for varying the rate of delivery of the pump in the sense of diminishing the rate of delivery of the pump as the differential is increased, said first and second sensitive means being formed by a casing having a surface consisting of a first deformable diaphragm and partitioned in two half spaces by a second deformable diaphragm which is substantially parallel to said first diaphragm, the half space comprised between the two diaphragms being connected to the delivery duct of the pump, the other half space being connected to the initial portion of the exhaust piping, the diaphragms being mechanically interlinked and connected with said means for varying the rate of flow delivered through the delivery duct.

Claim 3

The internal combustion engine according to claim 1, characterized in that said first diaphragm has an area which is less than the area of the second diaphragm.

Claim 4

An internal combustion engine comprising an intake piping, an exhaust piping, a pump driven by the engine for drawing air from the atmosphere and discharging through a delivery duct the compressed air into said exhaust piping, means for varying the rate of delivery through said delivery duct, the improvement including first means sensitive to the differential between the pressure in the delivery duct of the pump and the pressure in the exhaust piping, said first means being connected to said means for varying the rate of delivery in the sense of diminishing said rate of flow as said differential is increased, and second means sensitive to the differential between one at least of said pressures in the exhaust piping and in the delivery duct and the outside atmosphere pressure; said second means being connected to said means for varying the rate of delivery in the sense of diminishing the rate of delivery of the pump as said differential is increased; and a member sensitive to the power delivered by the engine to control said means for varying the rate of delivery in the sense of minimizing said rate of delivery when the delivered power of the engine exceeds a preselected value.

Claim 5

An internal combustion engine comprising an intake piping, an exhaust piping, a pump driven by the engine for drawing air from the atmosphere and discharging through a delivery duct the compressed air into said exhaust piping, means for varying the rate of delivery through said delivery duct, the improvement including first means sensitive to the differential between the pressure in the delivery duct of the pump and the pressure in the exhaust piping, said first means being connected to said means for varying the rate of delivery in the sense of diminishing said rate of flow as said differential is increased, and second means sensitive to the differential between one at least of said pressures in the exhaust piping and in the delivery duct and the outside atmosphere pressure; said second means being connected to said means for varying the rate of delivery in the sense of diminishing the rate of delivery of the pump as said differential is increased; and a member sensitive to the power delivered by the engine to control said means for varying the rate of delivery in the sense of minimizing said rate of delivery when the delivered power of the engine exceeds a preselected value.

Claim 6

An internal combustion engine comprising an intake piping, an exhaust piping, a pump driven by the engine for drawing air from the atmosphere and discharging through a delivery duct the compressed air into said exhaust piping, means for varying the rate of delivery through saiD delivery duct, the improvement including first means sensitive to the differential between the pressure in the delivery duct of the pump and the pressure in the exhaust piping, said first means being connected to said means for varying the rate of delivery in the sense of diminishing said rate of flow as the differential is increased, second means sensitive to the differential between one at least of said pressures in the exhaust piping and in the delivery duct and the outside atmosphere pressure; said second means being connected to said means for varying the rate of delivery of the pump in the sense of diminishing the rate of delivery of the pump as the differential is increased, a member sensitive to the power delivered by the engine to control said means for varying the rate of delivery in the sense of minimizing the rate of delivery when the delivered power of the engine exceeds a preselected value, said exhaust duct comprising a first duct at least partially parallel to a second duct in which a device is inserted which is a catalyst of the postcombustion of the exhaust gases, said second duct offering a resistance to gas flow which is greater than the resistance offered by said first duct, valve means to control the gas flow through said first and said second ducts, and a device sensitive to the power delivered by the engine controlling said valve means in the sense of sending the exhaust gases into said first duct when the power delivered by the engine exceeds a preselected value and into said second duct when the power is below said value.

Claim 7

An internal combustion engine comprising an intake piping, an exhaust piping, a pump driven by the engine for drawing air from the atmosphere and discharging through a delivery duct the compressed air into said exhaust piping, means for varying the rate of delivery through saiD delivery duct, the improvement including first means sensitive to the differential between the pressure in the delivery duct of the pump and the pressure in the exhaust piping, said first means being connected to said means for varying the rate of delivery in the sense of diminishing said rate of flow as the differential is increased, second means sensitive to the differential between one at least of said pressures in the exhaust piping and in the delivery duct and the outside atmosphere pressure; said second means being connected to said means for varying the rate of delivery of the pump in the sense of diminishing the rate of delivery of the pump as the differential is increased, a member sensitive to the power delivered by the engine to control said means for varying the rate of delivery in the sense of minimizing the rate of delivery when the delivered power of the engine exceeds a preselected value, said exhaust duct comprising a first duct at least partially parallel to a second duct in which a device is inserted which is a catalyst of the postcombustion of the exhaust gases, said second duct offering a resistance to gas flow which is greater than the resistance offered by said first duct, valve means to control the gas flow through said first and said second ducts, and a device sensitive to the power delivered by the engine controlling said valve means in the sense of sending the exhaust gases into said first duct when the power delivered by the engine exceeds a preselected value and into said second duct when the power is below said value.

Claim 8

The internal combustion engine according to claim 4 characterized in that means sensitive to the temperature of the gases are arranged in the second exhaust duct downstream of the catalyst device for controlling said valve means in the sense of sending the exhaust gases into the first duct when the temperature is above a preselected value.